doc: add links to Errors.md

README.md

@@ -148,7 +148,7 @@ matters to you.
 * <a href="https://github.com/fastify/fastify/blob/master/docs/Lifecycle.md"><code><b>Lifecycle</b></code></a>
 * <a href="https://github.com/fastify/fastify/blob/master/docs/Reply.md"><code><b>Reply</b></code></a>
 * <a href="https://github.com/fastify/fastify/blob/master/docs/Request.md"><code><b>Request</b></code></a>
-* <a href="https://github.com/fastify/fastify/blob/master/docs/Error-Handling.md"><code><b>Error Handling</b></code></a>
+* <a href="https://github.com/fastify/fastify/blob/master/docs/Errors.md"><code><b>Errors</b></code></a>
 * <a href="https://github.com/fastify/fastify/blob/master/docs/ContentTypeParser.md"><code><b>Content Type Parser</b></code></a>
 * <a href="https://github.com/fastify/fastify/blob/master/docs/Plugins.md"><code><b>Plugins</b></code></a>
 * <a href="https://github.com/fastify/fastify/blob/master/docs/Testing.md"><code><b>Testing</b></code></a>

docs/Errors.md

@@ -1,89 +1,101 @@
 <h1 align="center">Fastify</h1>
 
-<a id="fastify-error-codes"></a>
-## Fastify Error Codes
+<a id="errors"></a>
+## Errors
 
-<a id="FST_ERR_CTP_ALREADY_PRESENT"></a>
-### FST_ERR_CTP_ALREADY_PRESENT
+<a name="error-handling"></a>
+### Error Handling
+
+Uncaught errors are likely to cause memory leaks, file descriptor leaks and other major production issues. [Domains](https://nodejs.org/en/docs/guides/domain-postmortem/) were introduced to try fixing this issue, but they did not. Given the fact that it is not possible to process all uncaught errors in a sensible way, the best way to deal with them at the moment is to [crash](https://nodejs.org/api/process.html#process_warning_using_uncaughtexception_correctly). In case of promises, make sure to [handle](https://nodejs.org/dist/latest-v8.x/docs/api/deprecations.html#deprecations_dep0018_unhandled_promise_rejections) errors [correctly](https://github.com/mcollina/make-promises-safe).
+
+Fastify follows an all-or-nothing approach and aims to be lean and optimal as much as possible. Thus, the developer is responsible for making sure that the errors are handled properly. Most of the errors are usually a result of unexpected input data, so we recommend specifying a [JSON.schema validation](https://github.com/fastify/fastify/blob/master/docs/Validation-and-Serialization.md) for your input data.
+
+Note that, while Fastify doesn't catch uncaught errors for you, if routes are declared as `async`, the error will safely be caught by the promise and routed to the default error handler of Fastify for a generic `Internal Server Error` response. For customizing this behaviour, you should use [setErrorHandler](https://github.com/fastify/fastify/blob/master/docs/Server.md#seterrorhandler).
+
+<a name="fastify-error-codes"></a>
+### Fastify Error Codes
+
+<a name="FST_ERR_CTP_ALREADY_PRESENT"></a>
+#### FST_ERR_CTP_ALREADY_PRESENT
 
 The parser for this content type was already registered.
 
-<a id="FST_ERR_CTP_INVALID_TYPE"></a>
-### FST_ERR_CTP_INVALID_TYPE
+<a name="FST_ERR_CTP_INVALID_TYPE"></a>
+#### FST_ERR_CTP_INVALID_TYPE
 
 The content type should be a string.
 
-<a id="FST_ERR_CTP_EMPTY_TYPE"></a>
-### FST_ERR_CTP_EMPTY_TYPE
+<a name="FST_ERR_CTP_EMPTY_TYPE"></a>
+#### FST_ERR_CTP_EMPTY_TYPE
 
 The content type cannot be an empty string.
 
-<a id="FST_ERR_CTP_INVALID_HANDLER"></a>
-### FST_ERR_CTP_INVALID_HANDLER
+<a name="FST_ERR_CTP_INVALID_HANDLER"></a>
+#### FST_ERR_CTP_INVALID_HANDLER
 
 An invalid handler was passed for the content type.
 
-<a id="FST_ERR_CTP_INVALID_PARSE_TYPE"></a>
-### FST_ERR_CTP_INVALID_PARSE_TYPE
+<a name="FST_ERR_CTP_INVALID_PARSE_TYPE"></a>
+#### FST_ERR_CTP_INVALID_PARSE_TYPE
 
 The provided parse type is not supported. Accepted values are `string` or `buffer`.
 
-<a id="FST_ERR_CTP_BODY_TOO_LARGE"></a>
-### FST_ERR_CTP_BODY_TOO_LARGE
+<a name="FST_ERR_CTP_BODY_TOO_LARGE"></a>
+#### FST_ERR_CTP_BODY_TOO_LARGE
 
 Request body is larger than the provided limit.
 
-<a id="FST_ERR_CTP_INVALID_MEDIA_TYPE"></a>
-### FST_ERR_CTP_INVALID_MEDIA_TYPE
+<a name="FST_ERR_CTP_INVALID_MEDIA_TYPE"></a>
+#### FST_ERR_CTP_INVALID_MEDIA_TYPE
 
 Received media type is not supported (i.e. there is no suitable content-type parser for it).
 
-<a id="FST_ERR_CTP_INVALID_CONTENT_LENGTH"></a>
-### FST_ERR_CTP_INVALID_CONTENT_LENGTH
+<a name="FST_ERR_CTP_INVALID_CONTENT_LENGTH"></a>
+#### FST_ERR_CTP_INVALID_CONTENT_LENGTH
 
 Request body size did not match Content-Length.
 
-<a id="FST_ERR_DEC_ALREADY_PRESENT"></a>
-### FST_ERR_DEC_ALREADY_PRESENT
+<a name="FST_ERR_DEC_ALREADY_PRESENT"></a>
+#### FST_ERR_DEC_ALREADY_PRESENT
 
 A decorator with the same name is already registered.
 
-<a id="FST_ERR_DEC_MISSING_DEPENDENCY"></a>
-### FST_ERR_DEC_MISSING_DEPENDENCY
+<a name="FST_ERR_DEC_MISSING_DEPENDENCY"></a>
+#### FST_ERR_DEC_MISSING_DEPENDENCY
 
 The decorator cannot be registered due to a missing dependency.
 
-<a id="FST_ERR_HOOK_INVALID_TYPE"></a>
-### FST_ERR_HOOK_INVALID_TYPE
+<a name="FST_ERR_HOOK_INVALID_TYPE"></a>
+#### FST_ERR_HOOK_INVALID_TYPE
 
 The hook name must be a string.
 
-<a id="FST_ERR_HOOK_INVALID_HANDLER"></a>
-### FST_ERR_HOOK_INVALID_HANDLER
+<a name="FST_ERR_HOOK_INVALID_HANDLER"></a>
+#### FST_ERR_HOOK_INVALID_HANDLER
 
 The hook callback must be a function.
 
-<a id="FST_ERR_LOG_INVALID_DESTINATION"></a>
-### FST_ERR_LOG_INVALID_DESTINATION
+<a name="FST_ERR_LOG_INVALID_DESTINATION"></a>
+#### FST_ERR_LOG_INVALID_DESTINATION
 
 Logger acceptes either a `'stream'` or a `'file'` as the destination.
 
-<a id="FST_ERR_REP_INVALID_PAYLOAD_TYPE"></a>
-### FST_ERR_REP_INVALID_PAYLOAD_TYPE
+<a name="FST_ERR_REP_INVALID_PAYLOAD_TYPE"></a>
+#### FST_ERR_REP_INVALID_PAYLOAD_TYPE
 
 Reply payload can either be a `string` or a `Buffer`.
 
-<a id="FST_ERR_SCH_MISSING_ID"></a>
-### FST_ERR_SCH_MISSING_ID
+<a name="FST_ERR_SCH_MISSING_ID"></a>
+#### FST_ERR_SCH_MISSING_ID
 
 The schema provided does not have `$id` property.
 
-<a id="FST_ERR_SCH_ALREADY_PRESENT"></a>
-### FST_ERR_SCH_ALREADY_PRESENT
+<a name="FST_ERR_SCH_ALREADY_PRESENT"></a>
+#### FST_ERR_SCH_ALREADY_PRESENT
 
 A schema with the same `$id` already exists.
 
-<a id="FST_ERR_SCH_NOT_PRESENT"></a>
-### FST_ERR_SCH_NOT_PRESENT
+<a name="FST_ERR_SCH_NOT_PRESENT"></a>
+#### FST_ERR_SCH_NOT_PRESENT
 
 No schema with the provided `$id` exists.